Blazor-SignalR tutorial updates for .NET 8

[guardrex]

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Document Details

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• ID: 85af7a99-672c-0438-dcc2-e8edfaf70c54
• Version Independent ID: 85af7a99-672c-0438-dcc2-e8edfaf70c54
• Content: Use ASP.NET Core SignalR with Blazor
• Content Source: aspnetcore/blazor/tutorials/signalr-blazor.md
• Product: aspnet-core
• Technology: aspnetcore-tutorials
• GitHub Login: @guardrex
• Microsoft Alias: riande